Warmbox receives mixed reviews from users. Some praise its ease of use, effective spam resolution, and helpful support, noting improvements in email deliverability and successful integration with Gmail. However, others criticize its limited email network reach, primarily focusing on Gmail, and report poor customer support and high pricing. Users have experienced issues with emails still landing in spam and difficulties in canceling subscriptions. While some find it beneficial for email marketing, others suggest exploring alternatives due to inconsistent results.